title: Environmentally friendly system for the degradation of multipesticide residues in aqueous media by the Fenton's reaction.
abstract: A Fenton oxidation system employing zero-valent iron (whose source was swarf, a residue of metallurgical industries, in powder form) and hydrogen peroxide for the treatment of an aqueous solution with six pesticides was developed, and the effect of the iron metal content, pH, and hydrogen peroxide concentration was evaluated. The characterization of the aqueous solution resulted in: pH 5.6, 105 mg L(-1) of dissolved organic carbon, and 44.6 NTU turbidity. In addition, the characterization of the swarf by FAAS and ICP-MS showed 98.43 ± 7.40 % of zero-valent iron. The removal was strongly affected by the content of iron metal, pH, and hydrogen peroxide concentration. The best degradation conditions were 2.0 g swarf, pH 2.0, and 5 mmol L(-1) H2O2. At the end of the treatment, the pesticide degradation ranged from 60 to 100%, leading to 55% mineralization. Besides, all hydrogen peroxide was consumed and the determination of total dissolved iron resulted in 2 mg L(-1). Thus, the advantages of this system are rapid degradation (up to 20 min), high-degradation rates, simple handling, and low cost.
authors.affiliation: Post-graduation Program in Technological and Environmental Chemistry, Escola de Química e Alimentos, Laboratório de Análise de Compostos Orgânicos e Metais (LACOM), Universidade Federal do Rio Grande, Av Itália, km 8, s/n, Rio Grande, 96201-900, Rio Grande do Sul, Brazil.
authors.forename: Bruno de S
authors.initials: Bde S
authors.lastname: Guimarães
authors.forename: Natiele
authors.initials: N
authors.lastname: Kleemann
authors.forename: Sergiane S
authors.initials: SS
authors.lastname: Caldas
authors.forename: Fabiane P
authors.initials: FP
authors.lastname: Costa
authors.forename: Maria A K
authors.initials: MA
authors.lastname: Silveira
authors.forename: Fabio A
authors.initials: FA
authors.lastname: Duarte
authors.forename: Ednei G
authors.initials: EG
authors.lastname: Primel
mesh_terms: D055772:Green Chemistry Technology / Q000379:methods*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction; D010573:Pesticide Residues / Q000032:analysis / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: C045076:Fenton's reagent; D010573:Pesticide Residues; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D007501:Iron